<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>demo</title>
    <style>
        div {
            position: fixed;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            font-size: 30px;
        }
    </style>
</head>

<body>
    <div>
        <a href="/static/keyboard.html" target="_parent">点击登录</a>
    </div>
</body>

</html>